The overall objective of this program is to develop high potency and stable polymer-coated digestive enzyme/bile acid-containing microspheres (DIGESTIZYME) for pancreatic enzyme deficient cystic fibrosis patients that is superior to the currently marketed digestive enzyme products. The objective of this Phase I proposal is to demonstrate the technical feasibility of preparing a high potency and stable DIGESTIZYME composition. The objective of the subsequent Phase II proposal is to demonstrate safety and clinical effectiveness of the DIGESTIZYME with pancreatic enzyme deficient cystic fibrosis patients. The specific aims of this Phase I proposal are to: 1. Investigate the compatibility and stability of high potency pancreatic enzyme powders, purchased from different manufacturers, for compatibility with bile acids and other formulation ingredients. 2. Develop prototype polymer-coated digestive enzyme/bile acid-containing microspheres. 3. Characterize the polymer-coated enzyme microspheres for integrity, enzyme potency and stability under simulated gastric and intestinal conditions. 4. Determine the kinetics of lipase, amylase, protease and bile acid release from the microspheres under simulated intestinal conditions. 5. Establish the long term stability of the polymer-coated enzyme microspheres under accelerated storage conditions.